Rotary boring-drill.



H. R. HUGHES. ROTARY BORING DRILL. APPLICATION FILED Nov. I9, |914.

Patented Nov. 27, 1917.

TTB STATE@ PATENT @FFTQEO f HOWARD JR'. HUGHES, OF HOUSTON, TEXAS,ASSIGNOR TO SHARP-HUGHES TOOL COMPANY, OFHOUSTON, TEXAS, AlC)0El?OBJEIOLT 0F TEXAS.

BOTABY BORING-DRILL.

Specication of Letters :Patent Patented Nov. 2'?, 191'?.

Original application led February 24, 1914, Serial No. 820,675. Dividedand this application led November 19, 1914. Serial No. 873,048.

To all whom t may concern.'

Be it known that I, HOWARD R. HUGHES, a citizen of the United States,residing at Houston, Texas, have invented a certain new and usefulImprovement in Rotary Boring-Drills, of which the following is a full,clear, and exact description, such as will enable others skilled in theart to which it .appertains to make and use the same.

This invention relates to rotary boring drills of the type in which thehead of the drill is provided with inclined side cutters that havecutting surfaces which remove the material from the side wall of thehole so as to maintain the clearance for the head of the drill, mypresent application being a division of my co-pending application Serial#820,675, filed February 24, 1914, now issued as Patent No. 1,124,445,January 12, 1915.

The main object of my present invention is to provide a drill of thegeneral type mentioned that is equipped with reversible side cutters ofnovel form that can be changed or arranged in a diierent position afterthe portions of same that act on the side Wall of the hole have becomeworn, thus bringing into service the portions of the said cutters thatare sufliciently sharp to remove the material from the side wall of thehole, and consequently, making it possible to use the drill for a longperiod without going to the trouble and expense of re-sharpening thecutters or renewing the cutters.

Another Objectis to provide a rotary boring drill that comprises meansVof novel construction' for retaining the cutters in operative positionon the head of the drill. @ther objects and desirable features of myinvention will be hereinafter pointed out.

Figure 1 of the drawings is a side elevational view of a drillconstructed in accordance with my invention;` and Figs. 2.and 3 aredetail sectional views illustratin different ways of mounting theinclined side cuttersf on the head of the drill.

Referrin to the drawings which illustrate one orm of-my invention, Adesignates two members that ,are clamped together to form the head ofthe drill and B designates a pair of inclined side cutters which revolvein planes that converge 'in the head of the drill and which are arrangedon opposite sides of a horizontally-disposed cutting device C, shownpartly in full lines and in broken lines in Fig. 1, that extendstransversely across the head of the drill and which is rotatably mountedon a horizontally-disposed shaft 1. One of the inclined side cutters Bis rotatably mounted on each section or part A of the head, and each ofsaid parts or sections A is provided with a pair of integral arms orprojections 2 which coperate with similar'portions on the other sectionof the head to form bear-l ings for the opposite ends of the cross shaft1, the two sections or parts A of the head being clamped .together bymeans of a coupling sleeve 3 or secured together in any other suitablemanner.

Each of the inclined side cutters B is provided with two oppositelyinclined beveled cutting portions 6 of the same angle and the samecutting area that are arranged on opposite sides of a cylindricalcutting portion 6a, thereby forming a symmetrical cutter which can bereversed after the beveled portion 6 on one side of same that acts onthe side of the hole and which is subjected to the greatest wear hasbecome worn. The cutter has a cylindrical body of substantially diskshape and said cutting surfaces are formed by chisel teeth that extendtransversely across the edge of said body substantially parallel to theaxis of rotation of the cutter. This is a very desirable feature of arotary boring drill, for it overcomes the necessity of re-sharpening theside cutte/rs or substituting new side cut-ters after the cuttingsurfaces of said cutters which act on the side wall of the hole andmaintain the clearance for the drill head have become worn to such adegree that the drill loses its clearance. It is true, of course, thatthe beveled portions of the side cutters B which. act on the bottom ofthe hole are subjected to some Wear, but

these portions of the cutters are not submove the material from the sidewall of the hole and thus maintain the clearance for would wear down andthus prevent the un-l Worn portions of the cutter from cutting properly.Therefore, side cutters B of the deslgn herein shown have two verydesirable characteristics, namely, they are free from sharp-pointed edgeportions which wear out quickly, and they can be reversed after theportions of same which are subjected to the greatest wear have becomeworn so as to bring into service the cutting portions of same which arestill sufficiently sharp to maintain the clearance for the head.

The inclined side cutters B can be mounted on the head of the drill invarious ways without departing from the spirit of my invention. In theconstruction illustrated in Fig. 2 the cutter is rotatably mounted on acylindricalshaped bushin 10 that is screwed onto an integral spindle 11on the head, and an enlarged cap or end piece 12 is formed at the outerend of said bushing so as to lap over the cutter, the cutter preferablybeing provided in its outer face with a recess for receiving theenlarged cap or end piece 12 on the bushing. A similar recess is formedin the opposite side of the 'cutter to receive avwasher 13 that ismounted on the integral spindle 11 on the head and which prevents thisside or face of the cutter from bearing directly against thel head ofthe drill, said Washer coperating with the bushing 10 to form asubstantially spool-shaped bearing for the cutter. In the formillustrated in Fig. 3 the cutter is rowasher 18 which is seated in arecess formed y in the outer face or side of the cutter. Both oftheconstructions illustrated in. Figs. 2 and 3 form eiicient mountings forreversible cutters, as they provide large bearing surfaces for thecutters of substantially spool shape and permit the cutters to bereversed quickly. A lubricant holder D is mounted on the head of thedrill in such a manner that it projects forwardly into the drill stem Eto which the drill 1s connected, and lubricatingducts 19 are formed inthe head so as to supply the lubricating` medium to distributing ducts20 formed in the spindles for the inclined side cutters.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is:

A rotary boring drill provided with areversible inclined side cutterthat acts on the bottom of the hole and also simultaneously removes thematerial from the side of the hole so as to maintain the clearance forthe head, said cutter having a cylindrical body of substantially diskform that is provided on its periphery with transversely-disposed teeththat extend parallel to the axis of rotation of the cutter, the endportions of said teeth being oppositely beveled at the same angle,thereby producing a symmetrical cutter that can be reversed after theportion of same that maintains the clearance for thehead has becomeworn.

In testimony whereof I hereunto aix my signature in the presence of twowitnesses, this fourteenth day of November, 1914.

HOWARD R. HUGHES.

Witnesses:

C. E. REED, S. EPs'rEIN.

